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Objective: To measure and determine the occupational cardiovascular workload and cardiovascular fitness among older employees (50 +) in four physically demanding occupational groups.

Methods: Health investigations, including aerobic capacity, were performed on 120 construction and kitchen workers, cleaners, and assistant nurses. Cardiovascular load was assessed over three working days using heart rate (HR) measurements. Data was processed for average loads (HR and Relative HR reserve (%HRR)) and measures describing variations in loads, such as time spent in different heart rate intensities.

Results: Participants’ mean age was 57 (SD 4.1) years, and 63% of the participants were female. The mean %HRR over occupational groups was 24.9% (SD 6.8). Of the participants, 43% had an average cardiovascular load above 24.5%HRR and 11% over 33%HRR. Depending on the work sector, 22–37% of the worktime was spent in intensities over 30%HRR, and 2–4% was spent in cardiovascular intensities over 50%HRR. The average VO2max was 33.2 (SD 8.2) ml/kg/min for all, for men 39.0 (SD 7.0), and for women 29.8 (SD 6.9).

Conclusion: We found a high mean cardiovascular load at work among the senior workers in all four work sectors, but low proportions of the worktime were spent in high intensity levels. Despite a high mean cardiovascular load at work, a high proportion of the workers had low cardiovascular fitness. Given the possible negative effects of occupational physical activity and to meet future demographic challenges, future interventions should aim to reduce physical loads and increase physical fitness in the workforce.

Objectives: To prospectively determine the association between occupational biomechanical exposures and the incidence of surgically treated carpal tunnel syndrome (CTS) in Swedish male construction workers.

Methods: A cohort of 203 866 Swedish male construction workers who participated in a national occupational health surveillance programme between 1971 and 1993 were followed for CTS surgery between 2001 and 2019. Age, height, weight, smoking status and construction trade were obtained from programme records. CTS surgery cases were defined using the diagnostic code for CTS and surgical procedure code for peripheral median nerve decompression in the Swedish National Patient Register. Biomechanical exposure estimates were assigned by trade from a job-exposure matrix. The relative risk (RR) of CTS surgery for each biomechanical exposure was assessed with multivariable negative binomial regression modelling.

Results: The study included 3851 cases and the total incidence rate of CTS surgery was 137.6 cases per 100 000 person-years. Associations were found for upper extremity load (RR 2.6; 95% CI 2.2 to 3.0), repetitive wrist flexion and extension (RR 2.6; 95% CI 2.2 to 3.0), full wrist extension (RR 2.3; 95% CI 1.9 to 2.6), power grip (RR 2.5; 95% CI 2.2 to 2.9), pinch grip (RR 2.0; 95% CI 1.7 to 2.4), handheld tool use (RR 2.3; 95% CI 2.0 to 2.7) and hand-arm vibration exposure (RR 2.3; 95% CI 1.9 to 2.7).

Conclusions: Occupational upper extremity load and postural exposures were associated with increased risk for surgical treatment for CTS in this large construction worker cohort. Preventive actions and consideration of occupation on assessment are warranted.

Background: Contrary to leisure-time physical activity, high levels of occupational physical activity (OPA) have been linked to cardiovascular disease and mortality. Many occupations in the construction industry are known to have high levels of OPA.Aims This study investigated OPA and stroke mortality risk among 299 382 Swedish male construction workers.

Methods: OPA was derived from job titles and categorized as low, medium or high, and stroke mortality was ascertained via the Swedish National Cause of Death Register. The average follow-up was 24 years resulting in a total of 6.9 million person-years, during which 4606 participants died from stroke. Relative risks were estimated with robust Poisson regressions and adjusted for age, calendar year, body mass index and smoking.

Results: The relative risk for overall stroke mortality was higher in the medium and high OPA groups compared to the low OPA group [1.15 (1.04, 1.27) and 1.13 (1.04, 1.23), respectively], with no clear dose-response association. Age-stratified analyses showed that higher OPA increased stroke mortality risk in participants between 70 and 89 years. Participants with high versus low OPA had a higher risk of ischaemic stroke mortality [1.15 (1.01, 1.31)].

Conclusions: Construction workers with high OPA have a slight increase in overall stroke mortality, mainly after retirement. Contrary to leisure-time physical activity, high levels of occupational physical activity have been linked to an increased risk of cardiovascular disease and mortality. Construction workers in this study with medium and high occupational physical activity had higher stroke mortality than those with low occupational physical activity. However, there was no difference in stroke mortality between those with high and medium occupational physical activity.

OBJECTIVES: This study aimed to assess the associations between occupational biomechanical factors and occurrence of surgically treated lumbar disc herniation (LDH) and describe the consequences in terms of early exit from the labor market.

METHODS: A cohort of 262 850 male construction workers participating in a national occupational health surveillance program was followed prospectively for 33 years (1987-2019). Occupational biomechanical exposures were assessed by a job exposure matrix (JEM) based on specific occupational groups. Workers who underwent surgical treatment for LDH were identified from the national patient register and data on disability pension from the Swedish Social Insurance Agency. Poisson regression models were used to estimate relative risks (RR) and 95% confidence intervals (CI) for biomechanical exposures, adjusted for age, body mass index, smoking status, height and time period.

RESULTS: There were 2451 cases of surgical treatment for LDH and the incidence peaked at age 40-45 years. Increased risks were found for often lifting >25 kg (RR 1.77, 95% CI 1.06-2.94), extreme lumbar flexion/extension (RR 1.60, 95% CI 1.37-1.88) and high exposure to whole-body vibration (RR 1.32, 95% CI 1.05-1.65). Among cases, the mean age for exiting the labor market due to disability pension was 55.9 years for white-collar workers and 51.7 years for construction workers.

CONCLUSIONS: Occupational exposure to heavy lifting and working in non-neutral back postures was associated with increased risk of surgical treatment for LDH. Construction workers who have had surgery for LDH exited the labor market with disability pension earlier than white-collar workers.

OBJECTIVES: The study investigated the association between occupational biomechanical risk factors and the occurrence of thumb carpometacarpal joint osteoarthritis (CMC1 OA) in construction workers.

METHODS: Male construction workers (n=237 525), participating in a Swedish occupational surveillance programme between 1971 and 1993, were followed between 1997 and 2019. CMC1 OA diagnoses were identified through linkage with national medical registries. Job title, smoking status, height, weight and age were collected from the surveillance programme. A job exposure matrix (JEM) was developed with exposure estimates on biomechanical risk factors for each occupational group. Relative risk (RR) of CMC1 OA diagnosis was calculated using a Poisson regression model.

RESULTS: There was an increased risk of CMC1 OA for all biomechanical risk factors (RR range 1.3-1.5). Exposure-response patterns were seen for repetitive wrist flexion and extension (low: RR 1.30 (95% CI 1.07 to 1.59), moderate: 1.32 (95% CI 1.07 to 1.62), high: 1.45 (95% CI 1.19 to 1.75)), wrist extension (low: 1.31 (95% CI 1.09 to 1.59), moderate: 1.41 (95% CI 1.17 to 1.70) and heavy lifting (low: 1.13 (95% CI 0.92 to 1.38), moderate: 1.45 (95% CI 1.18 to 1.77), high: 1.50 (95% CI 1.24 to 1.82). Electricians (1.29 (95% CI 1.03 to 1.89)), concrete workers (1.31 (95% CI 1.02 to 1.67)), plumbers (1.37 (95% CI 1.07 to 1.76)), sheet-metal workers (1.58 (95% CI 1.18 to 2.10)), wood workers (1.66 (95% CI 1.36 to 2.03)), repairers (1.75 (95% CI 1.06 to 2.90)) and glass workers (2.21 (95% CI 1.42 to 3.44) had an increased risk of CMC1 OA compared with the reference group.

CONCLUSION: Wrist movements and hand loading were associated with CMC1 OA.

The primary aim of this study was to determine if occupational exposure to whole-body vibration (WBV) was associated with reporting neck pain. A cross-sectional study was conducted on a sample of the general population living in northern Sweden, aged 24-76 years. Data was retrieved through a digital survey that collected subjectively reported information on exposure to WBV and biomechanical exposures as well as neck pain. The study included 5,017 participants (response rate 44%). Neck pain was reported by 269 men (11.8%) and 536 women (20.2%). There was a statistically significant association between reporting occupational exposure to WBV half the time or more (adjusted OR 1.91; 95% CI 1.22-3.00) and reporting neck pain. In gender-stratified analyses, the same pattern was observed in men, while there were too few women to determine any association. We conclude that occupational exposure to whole-body vibration was associated with neck pain in men.

This mixed method study aimed to describe what risk-reducing actions were proposed by ergonomists after the execution of a guided process for occupational health surveillance for workers exposed to hand-intensive work in ten companies. Another aim was to describe the exposed workers' proposals for risk-reducing actions, including their perceptions of potential changes in the self-assessed exposure levels and work-related pain. Several actions, targeting organizational, technical, and/or individual measures were proposed. Proposals from the ergonomists more often targeted the personal measures, whereas the workers' proposals targeted technology or organizational changes. Six companies implemented at least one of the action proposals. These action proposals were not related to evaluation metrics, nor were they evaluated. This study indicates that both ergonomists and companies need guidance on how to improve to work in a participatory process for the implementation and evaluation of risk-reducing actions, e.g., by how to better include workers’ experiences.

Objectives: Physical and cognitive tasks occur together in many occupations. Previous reviews of combined tasks have mainly focused on their effects in a sports context. This review investigated to which extent combinations (concurrent or alternating) of occupationally relevant physical and cognitive tasks influence responses reflecting biomechanical exposure, stress, fatigue, performance, and well-being.

Methods: We searched Scopus, Pubmed, Cinahl, and Psychinfo for controlled experiments investigating the effects of combinations of occupationally relevant physical and cognitive tasks in participants aged 18 to 70. In total, we identified 12 447 records. We added recent papers that had cited these studies (n = 573) to arrive at a total of 13 020 publications. After screening for relevance, 61 studies remained, of which 57 were classified to be of medium or high quality. Of the 57 studies, 51 addressed concurrent tasks, 5 alternating tasks, and 1 both concurrent and alternating tasks. Results Most studies of concurrent physical and cognitive tasks reported negative effects, if numerically small, on indicators of biomechanical exposure, fatigue, and performance, compared to a physical task alone.

Results: were mixed for stress indicators, and well-being was too little studied to justify any conclusions. Effects depended on the tasks, including their intensity and complexity. Alternating physical and cognitive tasks did not appear to influence outcomes much, compared to having passive breaks in-between physical tasks.

Conclusions: The reviewed evidence indicated that concurrent physical and cognitive work tasks have negative, yet small effects on biomechanical indicators, fatigue and performance, compared to performing the physical task alone, but only if the physical task is intense, and the cognitive task is complex. Alternating between physical and cognitive tasks may have similar effects as breaking up physical tasks by passive breaks, but studies were few. Future studies should address ecologically valid combinations of physical and cognitive tasks, in particular in controlled field studies devoted to the long-term effects of combined work.

Background: Occupational cold exposure is common in Sweden but potential impacts on musculoskeletal disorders have not been thoroughly investigated. The primary aim of this study was to determine the associations between occupational contact and ambient cooling in relation to pain in the upper extremity.

Methods: In this cross-sectional study, a digital survey was conducted on a population-based sample of women and men between 24 and 76 years of age, living in northern Sweden. Occupational cold exposure, heavy manual handling, work with vibrating tools as well as the presence of upper extremity pain at different sites were subjectively reported. Associations between exposure and outcome were evaluated using multiple binary logistic regression.

Results: The final study sample included 2,089 (54.4%) women and 1,754 men, with a mean age of 56 years. Hand pain was reported by 196 (5.2%), lower arm pain by 144 (3.8%), and upper arm pain by 451 (11.9%). Severe ambient cooling for more than half of the working time was statistically significantly associated with hand pain (OR: 2.30; 95% CI: 1.23–4.29) and upper arm pain (OR: 1.57; 95% CI: 1.00–2.47) but not lower arm pain (OR: 1.87; 95% CI: 0.96–3.65) after adjusting for gender, age, body mass index, current daily smoking, heavy manual handling, and work with vibrating tools.

Conclusions: Occupational cold exposure was statistically significantly associated with hand pain and upper arm pain. Therefore, occupational cold exposure should be recognized as a potential risk factor for musculoskeletal disorders in the upper extremity.

OBJECTIVE: The aim of this study was to assess the association between occupational biomechanical exposures and the occurrence of surgical treatment for subacromial impingement syndrome (SIS).

METHODS: A cohort of 220 295 male constructions workers who participated in a national occupational health surveillance program (1971-1993) were examined prospectively over a 16-year follow-up period (2001-2016) for surgically treated SIS. Worker job title, smoking status, height, weight, and age were registered on health examination. Job titles were mapped to 21 occupational groups based on tasks and training. A job exposure matrix (JEM) was developed with exposure estimates for each occupational group. Surgical cases were determined through linkage with the Swedish national in- and outpatient registers. Poisson regression was used to assess the relative risks (RR) for each biomechanical exposure.

RESULTS: The total incidence rate of surgically treated SIS over the 16-year observation period was 201.1 cases per 100 000 person-years. Increased risk was evident for workers exposed to upper-extremity loading (push/pull/lift) (RR 1.45-2.30), high hand grip force (RR 1.47-2.23), using handheld tools (RR 1.52-2.09), frequent work with hands above shoulders (RR 1.62-2.11), static work (RR 1.77-2.26), and hand-arm vibration (RR 1.78-2.13). There was an increased risk for SIS surgery for all occupational groups (construction trades) compared with white-collar workers (RR 1.56-2.61).

CONCLUSIONS: Occupational upper-extremity load and posture exposures were associated with increased risk for surgical treatment of SIS, which underlines the need for reducing workplace exposures and early symptom detection in highly exposed occupational groups.